Tunable CO2 electroreduction to ethanol and ethylene with controllable interfacial wettability

Abstract

The mechanism of how interfacial wettability impacts the CO2 electroreduction pathways to ethylene and ethanol remains unclear. This paper describes the design and realization of controllable equilibrium of kinetic-controlled *CO and *H via modifying alkanethiols with different alkyl chain lengths to reveal its contribution to ethylene and ethanol pathways. Characterization and simulation reveal that the mass transport of CO2 and H2O is related with interfacial wettability, which may result in the variation of kinetic-controlled *CO and *H ratio, which affects ethylene and ethanol pathways. Through modulating the hydrophilic interface to superhydrophobic interface, the reaction limitation shifts from insufficient supply of kinetic-controlled *CO to that of *H. The ethanol to ethylene ratio can be continuously tailored in a wide range from 0.9 to 1.92, with remarkable Faradaic efficiencies toward ethanol and multi-carbon (C2+) products up to 53.7% and 86.1%, respectively. A C2+ Faradaic efficiency of 80.3% can be achieved with a high C2+ partial current density of 321 mA cm−2, which is among the highest selectivity at such current densities.

Ampere-Level CO2-to-Ethanol Conversion via Boron-Incorporated Copper Electrodes

“…Besides, a higher ratio of *CO atop /*CO bridge is obtained using the B–Cu HPE, which indicates that more *CO bridge converts into *CO atop (Figure S20b). These results show that *CO atop is essential for C–C coupling to obtain high FE C2+ and FE ethanol . ,− …”

Advances and challenges in membrane electrode assembly electrolyzers for CO2 reduction

“…79,80 However, there appears to be a trade-off between flooding resistance and mass transportation ability related to the structural parameters (such as thickness and cracks) of the GDE. 73 (2) Modify the GDE structure with hydrophobic additives, such as PTFE, 80,82,83 carbon black, 84 alkyl chains, 85,86 and so on. Adding PTFE has shown enhanced hydrophobicity in GDEs, either by mixing it with the catalyst, 82 embedding it in the microporous layer (MPL), 83 or applying it to the back of a macro-porous support.…”

Electrocatalytic Urea Synthesis via C–N Coupling from CO2 and Nitrogenous Species

“…Advanced characterization techniques can be used to detect crucial species and understand the electrocatalytic coupling reaction mechanisms. , Isotope-labeling operando synchrotron-radiation Fourier transform infrared spectroscopy (SR-FTIR) is performed in this C–N coupling system to monitor the formation and evolution of chemical bonds during the electrocatalytic process . As shown in Figure c, the stretching vibration of C–N at 1449 cm –1 emerges as solid evidence for the C–N coupling process.…”